Shoulder stock



FIG. 1 is a perspective view of a shoulder stock showing my new design in full lines with the broken line showing of environmental association matter being for illustrative purposes only and forming no part of the claimed invention;

FIG. 2 is a right side elevational view of the shoulder stock thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a shoulder stock, as show and described. 